THE LESSER OF TWO EVILS PROBLEM: If, say, a newly-pregnant woman has a disease which is always fatal – long before the fetus is viable outside the woman – but the treatment is a drug which always kills the fetus, the choice confronting the mother is saving just her life, or permitting both to die.
Under these circumstances, there is a moral obligation to kill the fetus by taking the drug.
The intent is to save the life of both; as Spirithound noted, this is the principle of double effect rather than a purposeful killing of the fetus (which is an abortion). This is far, far different than an intended abortion.
THE SOCIAL COMPACT PROBLEM: Occasionally, a pro-life sniper kills an abortion doctor. Objectively, such murders probably save lives in the immediately sense. The Church condemns murder of abortion doctors. When it does this, the Church is implicitly affirming the right of abortionists to pursue their trade until the power of persuasion results in a change of the law.
You’re kidding, right? The Church condemns murder in all forms. You would be correct if killing abortion doctors was the sole way of stopping abortions. But it is not, and your argument is non-sensical. If the Church were to advocate killing of abortion doctors, her stance would be hypocritical, no?
THE SUBTLE IMPLICIT
SUPPORT FOR ABORTION WITHIN THE CHURCH: It is not an accident that Roe v. Wade approved of abortions when it did. The Pill immensely popularized artificial birth control in Western culture, generating a very, very stubborn, almost-impossible-to-contest demand for “risk-free nookie” in Western culture. This immensely powerful bulldozer-like demand for “risk-free nookie” uses abortion as a “back-stop”: If the sexual promiscuity generated by the “risk-free nookie” ethos results in a pregnancy despite artificial birth control, the disappointed coiuple rush to kill the fetus.
Roe v. Wade comprised a caving-in to the enormous demand to kill offspring resulting from the ethos generated by newly-popular artificial birth control.
The Church quietly caves-in to the demand, exactly the way our society did with Roe v. wade, in another way.
Despite the fact that it has long been known that use of contraceptives ultimately generates the DEMAND for abortions,

That makes no sense. If contraceptives work, then there is no need for abortions.

though just about every Catholic parish has a pro-life budget, almost no parish has an anti-contraception budget, and aside from encouraging Natural Family Planning the church does not actually actively condemn use of contraceptives from the pulpit.
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